Process of extracting caffein.



H. TRILLICH.

PROCESS 0F EXTRAGTING CAFPBIN.

APPLIOATION FILED APR. 15, 10094 Patented Feb. 22, 1910.

"UNITED sTAtrnsaaENT OFFICE.

HEINBICH'TRILLICH, 0F MUNICH, GERMANY;

raocassA or nx'rnacrme emana.

Sp'eoication of Letters Patent.

Patented Feb. 22, 1910.

Application filed April 15, 1908. Serial N0. 490,161.

To all 'whom 'it may concern:

Be it known that I, HEINRICH TmLLIcH, a subject of the King of Bavaria, residing at 21 Prinzregentenplatz, Munich., Bavarian German have invented certain new and usefulprovements in Processes of Extracting Caffein from Coffee or from Similar Materials whichl Contain Catfein, of which the following is a specification.

This invention relates to a process of extracting caffein from unground raw coffee beansand also from other materials which contain caein, such process being very effective and furnishes within a short, time, a roduct which is sufficiently freed from caein without the loss of any aromatic or other useful ingredients of the coffee.

As is well known, the combinations between ca'ein and tannic acid or the like prevent the caifein from being totally extracted from the coffee and similar substances containing caffein and it has therefore been reco ized as necessary to dissociate such comblnations before a suiiicient extraction of the caifein can be obtained. Therefore t-he process in accordance with this invention aims to dissociate and extract the catl'ein from the coffee without diminishing the aroma or changing the taste of the coffee and further Without injuring the structure of the bean, and to obtain the foregoing objects the combinations between caffein and tannic acid are dissociated by means of electrolysis before the beginning of the extraction, it, however, has also been recognized as useful to form the dissociation by meansof electrolysis during the extraction with hot dissolvents, such as acetic ether,

' benzol, carbon tetrachlorid, ethane tetrachlorid, benzol dichlorid, chloroform, sulfuric ether, dichlorhydrin, epichlorhydrin, carbon sul-tid, ethylene trichlorid. It has furthermore been practicable to obtain the dissociation and extraction of the cafiein within` rotary boilers or wihin boilers with rotary anodes or rotary ca hodes to agitate the wet coffee. Using hot acetic ether as a dissolvent, a nearly complete extraction of thecaifein from unground raw coffee takes place with a five volts tension within twelve to eighteen hours, according to the weakness of the coffee beans. After having erformed the extraction, the residues of tie solvent which adhere to the coffee are evaporated in the usual manner.

.As illustrating one form of an apparatus in which the process in accordance with this Invention can be carried out reference is had tov'tlle accompanying drawing which illustrates the apparatus in longitudinal section.

Referringto the drawings in detail, dcnotes a rotary vessel which is provided with a heating jacket'b mounted u on rollers' c. The jacket b is connected con` uctively by a conduit ring d and a brush e with one electrode while the other electrode is connected by a brush fha contact rin g and a wire h, the latter being insulated om the vessel a, with a hollow body lc arranged within the vessel a and mounted on insulated supports e. The vessel a. with the jacket b is mounted upon the uprights n. Communicating with the interior of the vessel a are a pair of pipes which extend from and communicate with a reservoir fw.

The pipes are indicated by the reference characters o and o', the pipe o being arranged within the pipe o. The pipe vo communicates with the reservoir w throu l1 the port os and pocket 0*, that is to say, tie pipe o opens into the pocket 0*, the latter communicating with the reservoir v Qn through the port oi.' The pipe o extendsv in the pocket o4 and has its upper end ar-.

inner cooler being indicated by the reference'y character p and the outer cooler by the reference character g. lVithin the outer cooler l] is arranged a coil s which at its upper end communicates with the reservoir fw. said upper end being the inlet. of the coil and at its lower end communicates with the reservoir fw. said lower end being the out-let of the coil. The pipe 0 serves to conduct to the reservoir w the heat solvent vapors generated in the vessel a. The vapors pass up the pipe 0 into the pocket 04 and through the port o3 into t-he reservoir w where they are condensed, certain of the vapors pass off into the coil s and are condensed and discharged back into the reservoir 'u'. condensed vapors pass down into the pipo o and then are discharged into the vessel a.. The inner pipe o is, what may be termed, a

supply pipe for the extracting solvent and uring the assage of the extracting solvent through t 1e pipe o into the vessel a, in case the hot vapors are passing 'through the pipe o to the cooler, the solvent is moderately heated on its passage to the vessel a. The two plpes serve respectively for carryback the condensed solvent with the greatest possible economy of heat. Y

The cooling medium supply pipes are indicated by the reference characters s and .se and the outlet pipes b`y the reference characters si?, s4. j

' The manner of carrying out the rocess is as follows: 50 kg. of raw ungroun coffee beans are steeped in an open boiler for twelve hours, with twenty liters of water so that the Awater penetrates thoroughly into the beans and is evenly absorbed and distributed. The coffee so moistened is then iitrodu'cedinto the vessel a (the manhole used for such purpose is not shown), the apparatus is then revolved and during its revolution the thoroughly moistened beans are subjected to the electric current, in such case the current transverses the moistened coffee 4from the electrode 7c to the other electrode, (vessel a), the -current is furnished by a. dynamo machine of ten .volts tension. Such operation is carried on for about half an hour and `which dissociates the cafein from the tannic acid so that the extraction will. be facilitated. After the passage of the current for the period stated acetic ether is supplied to the vessel a through thel reservoir and pipe 0, the amount of the acetic ether being such as to about half fill the Avessel a, that is, about 50 liters. A heating medium is then supplied to the jacket I), so that the acetic ether comes to a boil. The vapors generated in the vessel a are conducted therefrom into the reservoir 'w through the pipe o Where they are con- 'densed and flow back through the pipe 0 into the vessel a. This operation is carried on for about three hours without the passage of the current. 'lhe acetic acid is then drawn off with the extracted caffein (through a drawcff cock not shown), and

transferred to a (listilling apparatus, where the acetic ether is dissolved off so that the caffeiu remains in a cencentrated aqueous solution. Now in the meanwhile acetic other is introduced into the vessel a until it is about half full, the aceticv either heated again and the extraction carried on for 'about three hours, in which case, however,

. the electric current is caused to pass through the beans are then removed -froin the vessel a and freed in any suitable distilling or, drying V apparatus from the acetic ether and water that has been absorbed. For this purlpose if desired, the vessel a can be employed,

if it is employed, it is provided with suitable means for circulating therethrough a heatin medium, such as hot air or steam.

en the moistened beans'are sub'ected to the electric current, the caffein an nic acid combinations are dissociated Whereby the extraction of the'caffein is facilitated when the beans are again subjected to acetic ether.

The acetic ether used for extraction. is freed by distillation from the caffein and used over and over again.

It has been found generally that the; moistening of the beans by water is sufficient for the conducting of the current,however,

.if it be not sufficient, an acid can be added Vto tanthe water which will then produce sufficient conductivity.

-What I claim is: i 1. Al process of extracting caffein from unground raw coffee comprising thethorough moistening of the coffee, then passing an electrical current through the mass'to dissociate the caffein from the tannic acid, then subjecting the coffee to a hot caffein extracting solvent whereby the caein is removed from the coffee while' at the same time leaving undissolved the aromatic and other ingredients of the coffee, and then removing the solvent adheringto the coffee.

2. A process of extractin caffein from unground raw coffee comprising the thorough moistening of the coffee, then passing an electrical current through the mass to dissociate the caffein from vthe, -tannie acid, then subjecting the" coffeeto a hot caffein 'extracting solvent whereby the caffein is removed from the coffee while at the same time leaving undissolved the' aromatic and other ingredients of the coffee, and then removing" the solvent adhering-to the coffee and maintaining the coffee in a state of agitation during the passage of the current and during the subjecting of the coffee to the solvent.

3. 'lhe process of extracting cafein from unground raw coffee comprising moistening the coffee, and then subjecting the coffee to electrolysis and an extracting solvent whereby the caffein is removed from the coffee, and then removing the solvent from the coffee.

In testimony whereof I affix my signature.

' HEINRICH TRILLICH.

In the presence of- Louis MUELLER, A MATHILDE K. HELD. 

